Ha-ha , Roma , it is very good ! ;-) I will make a good copper plate with this name and attach it to my phonostage ....... ;-)

Dima

hI bRIAN,

Brian Clark wrote:

The 834P was a revelation for me, being a circuit that I would have dismissed as "old hat" (Feedback? 12AX7 cathode follower? Do me a favour!).

Me too, but you know me, i'm mainly pragmatic. The EAR 834P is rather better than one would think, even with cheap parts, a testament to the skills of TdP.

Brian Clark wrote:

I like it so much that I intend to build an "enhanced" copy a la Thorsten/Carsten for reference (and enjoyment!) before investigating the high Gm alternative (D3a + E55L or E810F ) My step-ups will be S&B.

If you do, do seek out old Air dielectric AM tuning Capacitors. You only need 110pF & 330pF, both can be found suitably. Once you tuned the RIAA to perfection simply superglue the shaft in.... I used to use that trick in prototyping in the old days when tuning Op-Amp compensations and found circuits sounded better with those "Air Variable" capacitoirs than they did with good quality polystyrene for stabilisation.

Ciao T

Thorsten wrote:

If you do, do seek out old Air dielectric AM tuning Capacitors. You only need 110pF & 330pF, both can be found suitably. Once you tuned the RIAA to perfection simply superglue the shaft in.... I used to use that trick in prototyping in the old days when tuning Op-Amp compensations and found circuits sounded better with those "Air Variable" capacitoirs than they did with good quality polystyrene for stabilisation.

Brian,

I sourced the air caps from here:

http://www.oselectronics.com/ose_p96.htm

The AVC150 does a wonderful 110pF (I run it 112pF) and the BC14400 does good as 330pF. I did not lock them up but I do not shake them. The AVC150 has very stiff shaft, the BC14400 is very loose. However, I did not see that it drifted, although the corrector once was flying around in my car.

The only thing that you might want to do would be does not let the signal go via the bearing of the shat. In order to do so you would need to solder one contact to the default leg, however theanother one - do not connect to the chassis of the cap but to solder it to the movable plates. They are aluminum (you won’t find any cupper-made variable caps for 350pf) but with a strong solder gun (I use 200W) and long heating the thin aluminum will be solderable. Put some solder in the topmost movable plate, melt it, dial in the correct position of the shaft and then accurately solder a thin wire.

Be advised that although the 110pF EQ HF and 330pF EQ LF but it work reversing for sonic benefits. Changing of 110pF form polystyrene of mica to air (with the same value) will severally affect the quality of bass. Changing the 330pF form polystyrene of mica to air will very-very-very-very strongly affect the cleanness of HF and upper mid range.

Be carefully through, if you try those air caps once and recognize what they could do then you will stick them everywhere! I’m sticking them into my power amps, in any unnecessary and all-imaginary places, I try them on Cat and how I am working on a problem of a permanent attachment of those caps into my woman. I hope she will “sound better” after that… :-(

The caT

Hi All,

103 or 103R + mass loaded SME headshell + 3012 or a 3009 + Seiki 1500 + hagerman opamp phono stage (good only with select parts and battery power) or an EAR 834 (with some mods) and some old Altec mic transformers.  In that environment, it works quite ok...its quite a bit "harder" sounding on the opamp stage, but almost too slow on the 834. 

On either phono stage in any setup, I don't enjoy the higher frequencies.  They have a fairly improper spatial structure as compared to what I want/expect a cartridge to do.  This improper structure filters down and screws with mids too much for this to be for me the "end-all" cartridge.  This structure isn't so much an issue of "imaging" as its understood, but a lack of contrasty timber.  I want to say its too flat in tone, but that wording is too strong for my tastes.  On the other hand, an old Koetsu Black I had in this same setup (no heavy headshell), was WAY too imbued with an audible hue.

Since I often don't have the time (sometimes inclination) to alter sub 100% satisfactory results, I just keep playing the music I want without being too finicky.  Doing that, the plain 103 seems to distract me less than the 103R, but only with the opamp stage.  The 103R works better in those higher frequencies, but only well enough through the 834P.

They're both "good enough" cartridges for most people, and in the real world, a 200 buck cartridge that performs this well will make many people happy.  But that def should NOT preclude thinking on "what could be".

Your results may vary, but not by much :-)

Thinking what could be,

Chirag

BTW, my unbacked up HD crashed last week...can someone send/link me an 834P schema?  It would be rather appreciated.

Hi,

Chirag wrote:

103 or 103R + mass loaded SME headshell + 3012 or a 3009 + Seiki 1500 + hagerman opamp phono stage (good only with select parts and battery power) or an EAR 834 (with some mods) and some old Altec mic transformers.  In that environment, it works quite ok...its quite a bit "harder" sounding on the opamp stage, but almost too slow on the 834.

The EAR 834P is due to the use of "slow" and "veiled" sounding valves (ECC83's) a bit on the soft, slow and foggy sinde of the sound. That said, in many commercial (non-DIY) setups that is probably an asset.

Chirag wrote:

This structure isn't so much an issue of "imaging" as its understood, but a lack of contrasty timber.  I want to say its too flat in tone, but that wording is too strong for my tastes.

I have used the term "literal" previously to describe the 103. It is ultimatly more of a "truth" than "beauty" cartridge, no doubt a result of it's primarily pro heritage and one trait that actually agrees with me, due to also some pro background.

Chirag wrote:

They're both "good enough" cartridges for most people, and in the real world, a 200 buck cartridge that performs this well will make many people happy.  But that def should NOT preclude thinking on "what could be".

Absolutely agreed. I do not suggest that the 103 should be the only catridge you can have, but if you told me I can from now on only keep a SME 3009/10/12 Arm and Denon 103 on my turntable you probably do not get all that many complaints either.

I'd probably still prefer more choice, as I feel that as of now I have yet to hear "perfect" playback, so often it is preferable to have several arm/cartridge combo's available that have very contrasting sonic attributes and often cost all together less than top notch current "High-End" arms & cartridge combos and used judiciously can give better results for more records than a single combo

Chirag wrote:

BTW, my unbacked up HD crashed last week...can someone send/link me an 834P schema?  It would be rather appreciated.

You can e-mail for the original scan, otherwise look here:

http://www.jogis-roehrenbude.de/Leserbriefe/Carsten-RIAA/Carsten-RIAA.htm

This has a different powersupply and misses the component designations.

Ciao T

Chirag,

I have some other guys who were asking about the 834P schematic. I just got home and made a picture of my manual with the schematic in it. I do not know if it’s legal. It sort of none-commercial site and I did paid long time ago for my first unit and for the manual…  Besides, I have seen this it in many places around the web…

Anyhow, I would like to preface the image posting stating that the schema below is an intellectual property of EAR/Yoshino LTD.

Romy the Cat wrote:

Brian, I sourced the air caps from here: http://www.oselectronics.com/ose_p96.htm ... I am working on a problem of a permanent attachment of those caps into my woman. I hope she will “sound better” after that… :-( The caT

Hi Guy,

I know what you mean; this phono stage really should not work well at all.  I mean, voltage doubler, 3 stages of 12ax7, feedback, cathode followers, garbage looking power supply shared tubes for stereo...mortifying isn't it!  These facts actually kept me away from purchasing it for quite some time. OTOH, now I feel like this case, circuit boards, power supply and output tube can all be improved upon.

How about all of the T mods, Romy's air caps, a 6C45 6H30 6C19 type output tube with anode loading, external PS with bridged fast diodes, inductors and CRCRCR type dual power supply, inductors on a new parallel based heater supply, dual mono channels....goes on and on....no idea how all this would work though and it will definitely require some new cases.

Best,
Chirag

It's polishing a turd though isn't it? I listened to the 834 quite a bit when it came out and thought it sounded poor, even for the price. imho, The circuit's just bad.

If you do all that to it it isn't really an 834 anyway.

I used to work for a valve amp making company and we had a little 2 stage phono amp that sounded far better than the 834 with passive eq, no feedback etc. It also cost less than the EAR.

I can send you the schematic if you want to see it.

Hi Guy,

HAHAHA! yeah, I can see how you can say its similar to burnishing fecal matter.  i still think its overly pleasant slow sound (which is still ok through my headphone setup and denon 103) can be improved upon with major supply changes, but i'm not about to invest too much time doing it (not that i have any to waste).

Its quite a nice offer for the 2 stage schematic; my email can be accessed through my profile.

Best,

Chirag

guy sergeant wrote:

I used to work for a valve amp making company and we had a little 2 stage phono amp that sounded far better than the 834 with passive eq, no feedback etc. It also cost less than the EAR.I can send you the schematic if you want to see it.

guy sergeant wrote:

It's polishing a turd though isn't it? I listened to the 834 quite a bit when it came out and thought it sounded poor, even for the price. imho, The circuit's just bad. If you do all that to it it isn't really an 834 anyway. I used to work for a valve amp making company and we had a little 2 stage phono amp that sounded far better than the 834 with passive eq, no feedback etc. It also cost less than the EAR.

Guy, I would respectfully disagree with you about the 834P. Some people “who know” taught me about the benefits of open loop EQ in the feedback circuits. In the 834P the nature of the 12AX7 actually performs the necessary open loop EQ. There are many other thing in 834P that makes it attractive, however I certainly not a person who would dispute the circuitries….

Being a user, I have to tell that I do like the 834P. I like it either in it’s default unspoiled version, either as the Thorstened 834PT (which is way better). 834P certainly should have OK tubes in it, have no output attention and must not use the default EAR step-up transformer. Everything else, no mater how cheap and primitive it is would actually be capable to delivery very-very good result. Combined with a very good transformer I feel that it is one of the most musical phonostage I ever come across.

Pay attention, Guy, I’m not project how it performs based of my assessment of the circuits or after a few listening sessions but rather after years of living with it and years of RETURNING to it after many other, even better phonostages. Certainly there are many different solutions and methods how we can get deferent audio properties better then 834PT does. However, how necessary is it? I sincerely feel that 834PT do is absolutely enough for 95% installations and for 99.99999% of the listening musical demands. It is possible to push the envelope further but it is mostly unnecessary. I’m not kidding: I personally have a number of the phonostages but I would be perfectly fine to live with my ET2-2x834PT. Also, some other my phonostages do better in certain aspects but I still am not going to remove the 834PT from the active duty. It has something within it that is very right. It would be interesting if you elaborate on your vision were the 834PT is falling out performance-wise

In the end, one more comment in response to you post. I do not know why, but the became fashionable recently passive EQ, no feedback phonostages do not do a lot to me. Among what I heard form them they were all flat, with no space. The RLC passive were another story, however…

Rgs,
The Cat

Hi Romy,

I don't doubt for a moment that there are plenty of people 'who know' who will wax lyrical about the benefits of open loop eq in feedback circuits. There are people 'who know' who will tell me that valve amplifiers cannot be as good as transistor amplifiers and that transmission lines are the only way to get accurate bass from loudspeakers. Unfortunately I have to go to CES next month and will meet dozens of people 'who know' and who will proudly demonstrate their new mousetrap for me. Ultimately we have to base our opinions on what we hear, experience and find agreeable.

My experience with the 834p stemmed from having one at home for about a year soon after it was launched. I did try different types of ECC83 in it which did change it's balance slightly but not enough to make me like it.

My main problem with it was that it lacked clarity. Everything sounded smeared and hazy. It was overly euphonic (tubey) and fundamentally altered the timbre of instruments it set out to reproduce rendering all with the same signature of even order distortion. It also sounded slow and to my ears undynamic. I think it was moderately popular exactly because it sounded tubey and in most applications (ie as a substitute for the inbuilt phono stage in solid state pre-amps and integrated amps) it was preferable to what it replaced. In absolute terms, imho, it is a long way from being any sort of reference. However, it works for you and that's good.

I'm not really concerned whether passive eq no feedback pre-amps have recently become fashionable. I've been using them for 15-20 years. They've always sounded more natural to me. Most commercial implementations that I see are compromised in many ways, the most fundamental being power supply design.

I would like to try to build a equaliser using the Tango EQ600P LCR modules or the S&B equivalent. I heard one once and it did sound very promising.

Hi Guy,

guy sergeant wrote:

My experience with the 834p stemmed from having one at home for about a year soon after it was launched. I did try different types of ECC83 in it which did change it's balance slightly but not enough to make me like it. My main problem with it was that it lacked clarity. Everything sounded smeared and hazy. It was overly euphonic (tubey) and fundamentally altered the timbre of instruments it set out to reproduce rendering all with the same signature of even order distortion. It also sounded slow and to my ears undynamic.

Hmm, I'm allways being equally abused by one side for my audio absolutism (those are those who fail to read what I write well enough and presume anything I write is an absolute pronouncement and then find statements that appear to be contradicting each other) while the absolutists (among whom I am counting Romy I'm afraid) revile my Audio Relativism which allows that there is actually merit in items that are not too suited to their personal absolutes.

The EAR834P is such a case. I cannot quite relate either the enthusiam of Romy for the original and my mods, neither can I relate too well to your comments. I think it has merit and is a surprisingly effective piece of equipment, if you make sure to buy the cheapest version.

It is IMHO non too difficult to make a better phono stage, but in commercial terms, for the same money, with the kind of margins EAR USED TO give to dealers it would be a hard job.

In some ways the EAR 834P is the DENON DL103 of the Phonostages, to me, not the last word but used correctly it gets enough right that to spend more you need to get something of extremely higher performance, which tends to be not often available.

guy sergeant wrote:

I would like to try to build a equaliser using the Tango EQ600P LCR modules or the S&B equivalent. I heard one once and it did sound very promising.

S&B now has a 10K version of the same, I'm still waiting for my own, but using a 10K T-Network will make the overall design rather simpler that the 600R Impedance one. From those that have gone out and where phonostages have been build the general effect sonically seems identical to the 600R version.

Ciao T

guy sergeant wrote:

I don't doubt for a moment that there are plenty of people 'who know' who will wax lyrical about the benefits of open loop eq in feedback circuits. There are people 'who know' who will tell me that valve amplifiers cannot be as good as transistor amplifiers and that transmission lines are the only way to get accurate bass from loudspeakers. Unfortunately I have to go to CES next month and will meet dozens of people 'who know' and who will proudly demonstrate their new mousetrap for me.

guy sergeant wrote:

My main problem with it was that it lacked clarity. Everything sounded smeared and hazy. It was overly euphonic (tubey) and fundamentally altered the timbre of instruments it set out to reproduce rendering all with the same signature of even order distortion. It also sounded slow and to my ears undynamic.

guy sergeant wrote:

I would like to try to build a equaliser using the Tango EQ600P LCR modules or the S&B equivalent. I heard one once and it did sound very promising.

Thorsten wrote:

The EAR834P is such a case. I cannot quite relate either the enthusiam of Romy for the original and my mods.

Thorsten wrote:

S&B now has a 10K version of the same, I'm still waiting for my own, but using a 10K T-Network will make the overall design rather simpler that the 600R Impedance one. From those that have gone out and where phonostages have been build the general effect sonically seems identical to the 600R version.

The Cat

guy sergeant wrote:

I'm not really concerned whether passive eq no feedback pre-amps have recently become fashionable. I've been using them for 15-20 years. They've always sounded more natural to me. Most commercial implementations that I see are compromised in many ways, the most fundamental being power supply design.

Wow, how much better would the audio magazines be if we didn't have to tolerate the cliched and ill informed appraisals we are normally subjected to?! I completely understand how you perceived the sound of your Lamm experience from this image.

I'd get much more from reviewers if they communicated like this.

It would be quicker to read the trashy rags aswell! (not that I really ever bother)

I shall be hunting for a suitable image to conjure up my impression of the 834. A rustic scene perhaps. Taken from the lid of a biscuit tin or festive box of chocolates.

An interesting devise, They allow to adjust the midle point of the RIAA curve. I never have seen it and I wonder why would it be necessary or desierable?

http://www.gha.com.au/pdf/JPA66flyerPrelfVE.pdf

http://www.toneimports.com/emt/jpa66.html

http://www.electori.co.jp/EMT/JPA66.pdf

Romy the Cat wrote:

An interesting devise, They allow to adjust the midle point of the RIAA curve. I never have seen it and I wonder why would it be necessary or desierable?

Well, a range of mono EQ curves (and only Mono) had turnovers other than 500Hz (AES with 400Hz comes to mind, often used by Rudy van Gelder and then there was Decca with a different turnover each year in the 1950's!). 

AMR's PH-77 also adjusts the middle turnover for such curves. It is quite audible. Lest I am totally mistaken, the FM Acoustic Phonostage with adjustable EQ also adjusts this.

Ciao T

Thorsten wrote:

Well, a range of mono EQ curves (and only Mono) had turnovers other than 500Hz (AES with 400Hz comes to mind, often used by Rudy van Gelder and then there was Decca with a different turnover each year in the 1950's!).  AMR's PH-77 also adjusts the middle turnover for such curves. It is quite audible. Lest I am totally mistaken, the FM Acoustic Phonostage with adjustable EQ also adjusts this.

Romy the Cat wrote:

Hold on, are you saying that manufacturers of phonostages who claim that they run RIAA curve with precision of 0.1db are full of shit? Ok, take the Fifths and do not answer this question.

Romy the Cat wrote:

I did not know that middle turnover was a subject of valiance. The curves themselves were pretty much random in that time but I was under impression that they all cross zero at fixed point. If it is not so then it would be VERY VERY difficult to set the proper equalization by ears only.